Currently, the usage of light emitting diode (LED) backlights in liquid crystal display panels has an over 90% penetration rate. A backlight module incorporating the LED backlight may be edge-lit or direct-lit. In the edge-lit LED backlight, LED light sources may be configured along the periphery of a light guide panel. After entering the light guide panel, the LED light is reflected and scattered by reflection films and reflection dots to light the back of the display panel. The drawbacks of the edge-lit LED backlight may include poor contrast and no local dimming. In the direct-lit LED backlight, the LED light sources may be configured directly on the back of the display panel. The direct-lit LED backlight may present images more accurately with vibrant colors and sharp contrast, thereby gradually dominating the market.
The direct-lit backlight module may often include a printed circuit board (PCB). A plurality of packaged LED chips may be configured on the PCB board. Light emitted from the LED chips may irradiate the LCD display panel to achieve the backlight function of lighting up the LCD display apparatus.
Generally, gaps may exist between adjacent LED chips in the LED direct-lit backlight module. When the LED chips emit light, brightness in the gap region may appear darker due to the absence of light illumination, thereby causing a so-called “Gypsophila” symptom. That is, the brightness is strong at the positions of the LED chips, and is weak in the gap regions between adjacent LED chips.
The disclosed LED backlight, backlight module, and display apparatus are directed to solve one or more problems set forth above and other problems.